Blast cleaning equipment using a suspension of abrasives in
water is exempt.

106.452. Dry Abrasive
Cleaning (Previously SE 102)

Any abrasive cleaning operation that will satisfy paragraph
(1) or (2) of this section is exempt:

(1) enclosed abrasive cleaning:

(A) the particulate matter emissions are evacuated through a
fabric filter with a maximum filtering velocity of 4.0 feet per
minute (ft/min) with mechanical cleaning or 7.0 ft/min with air
cleaning; and

(B) there are no visible fugitive emissions from the facility;

(2) outside blast cleaning:

(A) abrasive usage rate shall not exceed 150 tons per year, 15
tons per month, and one ton per day; and

(B) the blast cleaning is performed at least 500 feet from any
recreational area or residence or other structure not occupied or
used solely by the owner of the facility or the owner of the
property upon which the facility is located; and

(C) records shall be maintained of operating hours and
abrasive material usage; and

(D) before construction begins, the facility is registered
with the commission's Office of Air Quality in Austin using Form
PI-7; and

(E) before construction of the facility begins, written site
approval shall be received from the executive director.

106.453 Washing and Drying
of Glass and Metal (Previously SE 42)

Equipment used for washing or drying products fabricated from
metal or glass is exempt, provided no volatile organic materials
are used in the process and no oil or solid fuel is burned.

106.454 Degreasing Units
(Previously SE 107)

Any degreasing unit that satisfies the following conditions of
this section is exempt.

(1) The following general requirements are applicable to all
degreasers unless specifically exempted by the conditions of this
section.

(B) Waste solvent from all degreasing operations shall be
stored in covered containers, and be removed by a licensed disposal
service or until emptying into an authorized on-site waste
management facility.

(C) Porous or absorbent materials, such as cloth, leather,
wood, or rope shall not be degreased.

(D) Leaks shall be repaired immediately, or the degreaser
shall be shut down until repairs are completed.

(E) A permanent and conspicuous label summarizing proper
operating procedures to minimize emissions shall be posted on or
near the degreaser.

(F) Each unit, regardless of the county in which it is
located, shall meet the requirements of 115.412 and 115.415 of this
title (relating to Control Requirements and Alternate Control
Requirements).

(2) The following conditions apply only to remote reservoir
cleaners.

(A) The cleaner shall be designed to prevent exposure of the
solvent reservoir to the atmosphere except for the drain openings.
The drain openings shall not exceed 3.0% of the total cleaner open
area and shall under no conditions exceed 16 square inches.

(B) All solvent sprays shall be a solid fluid stream (not a
fine, atomized, or shower type spray) and at a minimal operating
pressure that is necessary to prevent excessive splashing, but not
to exceed ten pounds per square inch, gauge (psig).

(C) The true vapor pressure of the solvent shall not exceed
0.6 pounds per square inch, absolute (psia) as measured or
calculated at an operating temperature of 100 degrees Fahrenheit.

(D) The solvent shall not be heated.

(3) The following conditions apply only to cold solvent
cleaners.

(A) The cleaner shall have a freeboard that has a minimum
four-inch water cover or provides a freeboard ratio (the distance
from top of the solvent level to the top edge of the degreasing
tank divided by the degreaser width) equal to or greater than 0.7.
For water covers, the solvent must be insoluble in and heavier than
water.

(B) The unit shall be equipped with a cover which is closed
whenever parts are not being handled in the cleaner. Also, the
cover must be designed for easy one-handed operation if any of the
following conditions are present:

(i) the true vapor pressure of the solvent is greater than 0.3
psia as measured or calculated at 100 degrees Fahrenheit;

(ii) the solvent is agitated;

(iii) the solvent is heated.

(C) If a solvent spray is used, it shall be a solid fluid
stream (not a fine, atomized, or shower-type spray) with a minimal
operating pressure that is necessary to prevent splashing above the
acceptable freeboard. The operating pressure shall not exceed ten
psig.

(D) An internal-cleaned parts drainage rack or facility, for
enclosed draining under a cover, shall be provided. An
external-cleaned parts drainage rack or facility, for enclosed
draining under a cover, may be used if the vapor pressure of the
solvent is less than 0.6 psia at 100øF. In all cases, parts
shall be drained for at least 15 seconds or until dripping ceases.

(E) The Form PI-7 registration is not required if total
solvent makeup (gross usage minus waste disposal) is 110 gallons
per year (gallon/yr) or less.

(F) Total solvent makeup shall not exceed the following:

(i) chlorinated solvents - 660 gallons/yr;

(ii) all other solvents - 1,500 gallons/yr.

(4) The following conditions apply only to open top solvent
vapor degreasers.

(A) The surface area of the solvent shall not exceed 15 square
feet.

(B) The unit shall be equipped with a cover that can be opened
and closed easily without disturbing the vapor zone. If the
degreaser opening exceeds ten square feet, a powered cover shall be
required.

(C) The cover shall be closed at all times except when parts
are moved into and out of the degreaser.

(D) The unit shall be equipped with a properly sized
refrigerated chiller, or the unit shall have a freeboard ratio (the
distance from top of the vapor level to the top edge of the
degreasing tank divided by the degreaser width) equal to or greater
than 0.75.

(E) Exhaust ventilation for the unit shall operate between 50
and 65 cubic feet per minute (cfm) per square foot of degreaser
open area unless this conflicts with Occupational Safety and Health
Administration (OSHA) requirements. Ventilation fans or other
sources of air agitation shall not be operated near the degreaser
opening.

(F) The exhaust stacks shall discharge vertically with no
restrictions or obstructions to flow. The stack height shall extend
at least 1.3 times the building height as measured from ground
level.

(A) The inlet and outlet openings shall be closed at all times
except when processing work through the degreaser.

(B) The unit shall be equipped with a properly sized
refrigerated chiller which has a volatile organic compound removal
efficiency of at least 85%, or the unit shall have a freeboard
ratio (the distance from top of the vapor level to the top edge of
the degreasing tank divided by the degreaser width) equal to or
greater than 0.75.

(C) A drying tunnel or other means of control shall be used to
limit liquid or vapor carry-out.

(D) Entrances and exits to the degreaser shall be designed to
silhouette work loads.

(E) Exhaust ventilation for the unit shall operate between 50
and 65 cfm per square foot of degreaser opening unless this
conflicts with OSHA requirements. Ventilation fans or other sources
of air agitation shall not be operated near the degreaser openings.

(F) The exhaust stacks shall discharge vertically with no
restrictions or obstructions to flow. The stack height shall extend
at least 1.5 times the building height as measured from ground
level.